OnePress Footer

Hello im really noob, would like to ask for some help, can anyone help me? How to change the footer color of Onepress theme to an image?

I cant replace or add within this default Onepress theme code from Footer.php

?>
 <footer id="colophon" class="site-footer" role="contentinfo">

        <?php

        $onepress_btt_disable = get_theme_mod('onepress_btt_disable');

        $onepress_social_footer_title = get_theme_mod('onepress_social_footer_title', esc_html__('Keep Updated', 'onepress'));

        $onepress_newsletter_disable = get_theme_mod('onepress_newsletter_disable', '1');

        $onepress_social_disable = get_theme_mod('onepress_social_disable', '1');

        $onepress_newsletter_title = get_theme_mod('onepress_newsletter_title', esc_html__('Join our Newsletter', 'onepress'));

        $onepress_newsletter_mailchimp = get_theme_mod('onepress_newsletter_mailchimp');

        if ( $onepress_newsletter_disable != '1' || $onepress_social_disable != '1' ) : ?>

            <div class="footer-connect">

                <div class="container">

                    <div class="row">

                        <div class="col-sm-2"></div>

                        <?php if ($onepress_newsletter_disable != '1') : ?>

                            <div class="col-sm-4">

                                <div class="footer-subscribe">

                                    <?php if ($onepress_newsletter_title != '') echo '<h5 class="follow-heading">' . $onepress_newsletter_title . '</h5>'; ?>

                                    <form novalidate="" target="_blank" class="" name="mc-embedded-subscribe-form" id="mc-embedded-subscribe-form" method="post"

                                          action="<?php if ($onepress_newsletter_mailchimp != '') echo $onepress_newsletter_mailchimp; ?>">

                                        <input type="text" placeholder="<?php esc_attr_e('Enter your e-mail address', 'onepress'); ?>" id="mce-EMAIL" class="subs_input" name="EMAIL" value="">

                                        <input type="submit" class="subs-button" value="<?php esc_attr_e('Subscribe', 'onepress'); ?>" name="subscribe">

                                    </form>

                                </div>

                            </div>

                        <?php endif; ?>

                        <div class="<?php if ( $onepress_newsletter_disable == '1' ) {

                            echo 'col-sm-8';

                        } else {

                            echo 'col-sm-4';

                        } ?>">

                            <?php

                            if ($onepress_social_disable != '1') {

                                ?>

                                <div class="footer-social">

                                    <?php

                                    if ($onepress_social_footer_title != '') echo '<h5 class="follow-heading">' . $onepress_social_footer_title . '</h5>';

                                    $socials = onepress_get_social_profiles();

                                    /**

                                     * New Socials profiles

                                     *

                                     * @since 1.1.4

                                     * @change 1.2.1

                                     */

                                    echo '<div class="footer-social-icons">';

                                    if ( $socials ) {

                                        echo $socials;

                                    } else {

                                        /**

                                         * Deprecated

                                         * @since 1.1.4

                                         */

                                        $twitter = get_theme_mod('onepress_social_twitter');

                                        $facebook = get_theme_mod('onepress_social_facebook');

                                        $google = get_theme_mod('onepress_social_google');

                                        $instagram = get_theme_mod('onepress_social_instagram');

                                        $rss = get_theme_mod('onepress_social_rss');

                                        if ($twitter != '') echo '<a target="_blank" href="' . $twitter . '" title="Twitter"><i class="fa fa-twitter"></i></a>';

                                        if ($facebook != '') echo '<a target="_blank" href="' . $facebook . '" title="Facebook"><i class="fa fa-facebook"></i></a>';

                                        if ($google != '') echo '<a target="_blank" href="' . $google . '" title="Google Plus"><i class="fa fa-google-plus"></i></a>';

                                        if ($instagram != '') echo '<a target="_blank" href="' . $instagram . '" title="Instagram"><i class="fa fa-instagram"></i></a>';

                                        if ($rss != '') echo '<a target="_blank" href="' . $rss . '"><i class="fa fa-rss"></i></a>';

                                    }

                                    echo '</div>';

                                    ?>

                                </div>

                            <?php } ?>

                        </div>

                        <div class="col-sm-2"></div>

                    </div>

                </div>

            </div>

        <?php endif; ?>